1. Field of the Invention
Various embodiments described herein are directed to distributed process control systems. More particularly, various embodiments are directed to determining and providing distributed control system hierarchical information to an asset management system.
2. Description of the Related Art
A growing trend in process control is distributed process control. Rather than having a single, centralized control center sending control commands to remote locations, the control functionality is moved closer to the controlled equipment. The centralized control center may then take a more supervisory role in the process control. For example, rather than sending a continuous stream of valve position commands to a valve controlling flow, the centralized control center may send a single flow set point to a remote process controller proximate to the valve, and allow the remote process controller to make valve position adjustments to achieve and maintain the desired flow. The data acquisition system may gather measurement data from field measurement and control equipment, and thus may be referred to as a supervisory control and data acquisition (SCADA) system.
Many of the commercially available field measurement and control equipment, such as remote process controllers and transmitters (e.g., pressure, flow, level, temperature), are implemented as microprocessor based devices. Because of the microprocessor based implementation, these devices may have the capability of digitally communicating status and configuration data about the devices themselves, in addition to their dedicated field task. The status and configuration data may be useful to a process engineer for tasks such as scheduling preventative maintenance and troubleshooting field equipment and/or processes.
In order to gather and possibly evaluate the status and configuration data, most process control systems implement an asset management system (AMS) in addition to one or more SCADA systems. An asset management system may communicate with field devices over the same communication channels as the SCADA system.
The hierarchical structure of a distributed process control system may be very complicated. For example, in a large petrochemical refinery, there may be tens, hundreds or thousands of remote process controllers reading measurement data from thousands of transmitters and controlling hundreds of devices which affect the state of the process, such as flow control valves, heaters, pumps, and the like. Similarly, yet more geographically diverse, a distributed control system may control hydrocarbon gathering across one or more hydrocarbon producing reservoirs, and thus may also employ tens or hundreds of remote process controllers and related equipment.
In the related art, for an asset management system to be usable, each and every piece of equipment for which the asset management system gathers status and configuration data has to be specifically entered into the database of the asset management system. Stated otherwise, unless the asset management system is told that a particular piece of field equipment exists on the network interconnecting various distributed control system components, the asset management system does not gather the status and configuration data about that particular piece of field equipment. Adding a piece of field equipment to an existing distributed process control system utilizing an asset management system may require a complete shutdown of at least the asset management system so that the hierarchy for the new equipment can be manually added to the asset management system's database. Manually entering data regarding the existence of each piece of field equipment, and that field equipment's location in the hierarchical structure of the process control system, is a tedious and time consuming venture.
Thus, what is needed in the art is a more efficient mechanism to gather hierarchical structure information, and to provide that information to an asset management system.